Considerations for a random access response for a two-step random access procedure

ABSTRACT

Various aspects of the present disclosure generally relate to wireless communication. A user equipment (UE) may transmit a random access message including a preamble and a payload. A base station may detect the preamble of the random access message. The base station, and may fail or succeed to decode the payload of the random access message. The base station may transmit, based at least in part on detecting the preamble and the different decoding outcome for the payload, a random access response. The random access response may include an uplink group grant and an indication for a type of the uplink group grant for a plurality of UEs whose preamble transmission share the same time and frequency occasion. UEs may monitor the type and the contents of the uplink group grant and transmit data subsequently on a set of shared time frequency resources. Numerous other aspects are provided.

CROSS-REFERENCE TO RELATED APPLICATION

This patent application claims priority to U.S. Provisional PatentApplication No. 62/859,604, filed on Jun. 10, 2019, entitled “DESIGNCONSIDERATIONS FOR RANDOM ACCESS RESPONSE FOR A TWO-STEP RANDOM ACCESSPROCEDURE,” and assigned to the assignee hereof. The disclosure of theprior application is considered part of and is incorporated by referencein this patent application.

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wirelesscommunication and to techniques and apparatuses for a random accessresponse for two-step random access procedure.

BACKGROUND

Wireless communication systems are widely deployed to provide varioustelecommunication services such as telephony, video, data, messaging,and broadcasts. Typical wireless communication systems may employmultiple-access technologies capable of supporting communication withmultiple users by sharing available system resources (e.g., bandwidth,transmit power, and/or the like). Examples of such multiple-accesstechnologies include code division multiple access (CDMA) systems, timedivision multiple access (TDMA) systems, frequency-division multipleaccess (FDMA) systems, orthogonal frequency-division multiple access(OFDMA) systems, single-carrier frequency-division multiple access(SC-FDMA) systems, time division synchronous code division multipleaccess (TD-SCDMA) systems, and Long Term Evolution (LTE).LTE/LTE-Advanced is a set of enhancements to the Universal MobileTelecommunications System (UMTS) mobile standard promulgated by theThird Generation Partnership Project (3GPP).

A wireless communication network may include a number of base stations(BSs) that can support communication for a number of user equipment(UEs). A user equipment (UE) may communicate with a base station (BS)via the downlink and uplink. The downlink (or forward link) refers tothe communication link from the BS to the UE, and the uplink (or reverselink) refers to the communication link from the UE to the BS. As will bedescribed in more detail herein, a BS may be referred to as a Node B, agNB, an access point (AP), a radio head, a transmit receive point (TRP),a New Radio (NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in varioustelecommunication standards to provide a common protocol that enablesdifferent user equipment to communicate on a municipal, national,regional, and even global level. New Radio (NR), which may also bereferred to as 5G, is a set of enhancements to the LTE mobile standardpromulgated by the Third Generation Partnership Project (3GPP). NR isdesigned to better support mobile broadband Internet access by improvingspectral efficiency, lowering costs, improving services, making use ofnew spectrum, and better integrating with other open standards usingorthogonal frequency division multiplexing (OFDM) with a cyclic prefix(CP) (CP-OFDM) on the downlink (DL), using CP-OFDM and/or SC-FDM (e.g.,also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) onthe uplink (UL), as well as supporting beamforming, multiple-inputmultiple-output (MIMO) antenna technology, and carrier aggregation.However, as the demand for mobile broadband access continues toincrease, there exists a need for further improvements in LTE and NRtechnologies. Preferably, these improvements should be applicable toother multiple access technologies and the telecommunication standardsthat employ these technologies.

SUMMARY

In some aspects, a method of wireless communication, performed by a userequipment (UE), may include transmitting a preamble and a payload of arandom access message associated with a two-step random accessprocedure; receiving a random access response, associated with thetwo-step random access procedure, including an uplink group grant and anindication of a type of the uplink group grant for a plurality of UEsincluding the UE; and transmitting an uplink communication on a set ofshared time-frequency resources based at least in part on the uplinkgroup grant.

In some aspects, a UE for wireless communication may include memory andone or more processors operatively coupled to the memory. The memory andthe one or more processors may be configured to transmit a preamble anda payload of a random access message associated with a two-step randomaccess procedure; receive a random access response, associated with thetwo-step random access procedure, including an uplink group grant and anindication of a type of the uplink group grant for a plurality of UEsincluding the UE; and transmit an uplink communication on a set ofshared time-frequency resources based at least in part on the uplinkgroup grant.

In some aspects, a non-transitory computer-readable medium may store oneor more instructions for wireless communication. The one or moreinstructions, when executed by one or more processors of a UE, may causethe one or more processors to: transmit a preamble and a payload of arandom access message associated with a two-step random accessprocedure; receive a random access response, associated with thetwo-step random access procedure, including an uplink group grant and anindication of a type of the uplink group grant for a plurality of UEsincluding the UE; and transmit an uplink communication on a set ofshared time-frequency resources based at least in part on the uplinkgroup grant.

In some aspects, an apparatus for wireless communication may includemeans for transmitting a preamble and a payload of a random accessmessage associated with a two-step random access procedure; means forreceiving a random access response, associated with the two-step randomaccess procedure, including an uplink group grant and an indication of atype of the uplink group grant for a plurality of apparatuses includingthe apparatus; and means for transmitting an uplink communication on aset of shared time-frequency resources based at least in part on theuplink group grant.

In some aspects, a method of wireless communication, performed by a basestation, may include detecting a preamble of a random access messageassociated with a two-step random access procedure, wherein the randomaccess message is received from a user equipment (UE); processing apayload of the random access message, wherein an outcome of processingthe payload is either successfully decoding the payload or failing todecode the payload; and transmitting, based at least in part ondetecting the preamble and the outcome of processing the payload, arandom access response associated with the two-step random accessprocedure, wherein the random access response includes an uplink groupgrant, and an indication of a type of the uplink group grant, for aplurality of UEs including the UE, wherein preamble transmissions of theplurality of UEs share a time and frequency occasion.

In some aspects, a base station for wireless communication may includememory and one or more processors operatively coupled to the memory. Thememory and the one or more processors may be configured to detect apreamble of a random access message associated with a two-step randomaccess procedure, wherein the random access message is received from auser equipment (UE); process a payload of the random access message,wherein an outcome of processing the payload is either successfullydecoding the payload or failing to decode the payload; and transmit,based at least in part on detecting the preamble and the outcome ofprocessing the payload, a random access response associated with thetwo-step random access procedure, wherein the random access responseincludes an uplink group grant, and an indication of a type of theuplink group grant, for a plurality of UEs including the UE, whereinpreamble transmissions of the plurality of UEs share a time andfrequency occasion.

In some aspects, a non-transitory computer-readable medium may store oneor more instructions for wireless communication. The one or moreinstructions, when executed by one or more processors of a base station,may cause the one or more processors to: detect a preamble of a randomaccess message associated with a two-step random access procedure,wherein the random access message is received from a user equipment(UE); process a payload of the random access message, wherein an outcomeof processing the payload is either successfully decoding the payload orfailing to decode the payload; and transmit, based at least in part ondetecting the preamble and the outcome of processing the payload, arandom access response associated with the two-step random accessprocedure, wherein the random access response includes an uplink groupgrant, and an indication of a type of the uplink group grant, for aplurality of UEs including the UE, wherein preamble transmissions of theplurality of UEs share a time and frequency occasion.

In some aspects, an apparatus for wireless communication may includemeans for detecting a preamble of a random access message associatedwith a two-step random access procedure, wherein the random accessmessage is received from a user equipment (UE); means for processing apayload of the random access message, wherein an outcome of processingthe payload is either successfully decoding the payload or failing todecode the payload; and means for transmitting, based at least in parton detecting the preamble and the outcome of processing the payload, arandom access response associated with the two-step random accessprocedure, wherein the random access response includes an uplink groupgrant, and an indication of a type of the uplink group grant, for aplurality of UEs including the UE, wherein preamble transmissions of theplurality of UEs share a time and frequency occasion.

In some aspects, a method of wireless communication, performed by a basestation, may include constructing an uplink group grant for a pluralityof UEs performing a two-step random access procedure, wherein preamblesor payloads of random access messages provided by the plurality of UEshave been detected by the base station; and transmitting a random accessresponse associated with the two-step random access procedure, whereinthe random access response includes the uplink group grant and anindication of a type of the uplink group grant.

In some aspects, a method of wireless communication, performed by a UE,may include transmitting a preamble and a payload of a random accessmessage associated with a two-step random access procedure; andreceiving a random access response associated with the two-step randomaccess procedure after transmitting the preamble and the payload of therandom access message, wherein the random access response includes anuplink group grant for a plurality of UEs including the UE, and whereinthe random access response includes an indication of a type of theuplink group grant.

In some aspects, a base station for wireless communication may include amemory and one or more processors operatively coupled to the memory. Thememory and the one or more processors may be configured to construct anuplink group grant for a plurality of UEs performing a two-step randomaccess procedure, wherein preambles or payloads of random accessmessages provided by the plurality of UEs have been detected by the basestation; and transmit a random access response associated with thetwo-step random access procedure, wherein the random access responseincludes the uplink group grant and an indication of a type of theuplink group grant.

In some aspects, a UE for wireless communication may include a memoryand one or more processors operatively coupled to the memory. The memoryand the one or more processors may be configured to transmit a preambleand a payload of a random access message associated with a two-steprandom access procedure; and receive a random access response associatedwith the two-step random access procedure after transmitting thepreamble and the payload of the random access message, wherein therandom access response includes an uplink group grant for a plurality ofUEs including the UE, and wherein the random access response includes anindication of a type of the uplink group grant.

In some aspects, a non-transitory computer-readable medium may store oneor more instructions for wireless communication. The one or moreinstructions, when executed by one or more processors of a base station,may cause the one or more processors to construct an uplink group grantfor a plurality of UEs performing a two-step random access procedure,wherein preambles or payloads of random access messages provided by theplurality of UEs have been detected by the base station; and transmit arandom access response associated with the two-step random accessprocedure, wherein the random access response includes the uplink groupgrant and an indication of a type of the uplink group grant.

In some aspects, a non-transitory computer-readable medium may store oneor more instructions for wireless communication. The one or moreinstructions, when executed by one or more processors of a UE, may causethe one or more processors to transmit a preamble and a payload of arandom access message associated with a two-step random accessprocedure; and receive a random access response associated with thetwo-step random access procedure after transmitting the preamble and thepayload of the random access message, wherein the random access responseincludes an uplink group grant for a plurality of UEs including the UE,and wherein the random access response includes an indication of a typeof the uplink group grant.

In some aspects, an apparatus for wireless communication may includemeans for constructing an uplink group grant for a plurality of UEsperforming a two-step random access procedure, wherein preambles orpayloads of random access messages provided by the plurality of UEs havebeen detected by the base station; and means for transmitting a randomaccess response associated with the two-step random access procedure,wherein the random access response includes the uplink group grant andan indication of a type of the uplink group grant.

In some aspects, an apparatus for wireless communication may includemeans for transmitting a preamble and a payload of a random accessmessage associated with a two-step random access procedure; and meansfor receiving a random access response associated with the two-steprandom access procedure after transmitting the preamble and the payloadof the random access message, wherein the random access responseincludes an uplink group grant for a plurality of UEs including theapparatus, and wherein the random access response includes an indicationof a type of the uplink group grant.

Aspects generally include a method, apparatus, system, computer programproduct, non-transitory computer-readable medium, user equipment, basestation, wireless communication device, and processing system assubstantially described herein with reference to and as illustrated bythe accompanying drawings and specification.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the scope of the appended claims. Characteristics of theconcepts disclosed herein, both their organization and method ofoperation, together with associated advantages will be better understoodfrom the following description when considered in connection with theaccompanying figures. Each of the figures is provided for the purposesof illustration and description, and not as a definition of the limitsof the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the above-recited features of the present disclosure can beunderstood in detail, a more particular description, briefly summarizedabove, may be had by reference to aspects, some of which are illustratedin the appended drawings. It is to be noted, however, that the appendeddrawings illustrate only certain typical aspects of this disclosure andare therefore not to be considered limiting of its scope, for thedescription may admit to other equally effective aspects. The samereference numbers in different drawings may identify the same or similarelements.

FIG. 1 is a block diagram conceptually illustrating an example of awireless communication network, in accordance with various aspects ofthe present disclosure.

FIG. 2 is a block diagram conceptually illustrating an example of a basestation in communication with a UE in a wireless communication network,in accordance with various aspects of the present disclosure.

FIGS. 3A-3C are diagrams illustrating examples associated with a randomaccess response for a two-step random access procedure, in accordancewith various aspects of the present disclosure.

FIG. 4 is a diagram illustrating example processes performed, forexample, by a base station, in accordance with various aspects of thepresent disclosure.

FIG. 5 is a diagram illustrating example processes performed, forexample, by a UE, in accordance with various aspects of the presentdisclosure.

FIG. 6 is a diagram illustrating example processes performed, forexample, by a base station, in accordance with various aspects of thepresent disclosure.

FIG. 7 is a diagram illustrating example processes performed, forexample, by a UE, in accordance with various aspects of the presentdisclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafterwith reference to the accompanying drawings. This disclosure may,however, be embodied in many different forms and should not be construedas limited to any specific structure or function presented throughoutthis disclosure. Rather, these aspects are provided so that thisdisclosure will be thorough and complete, and will fully convey thescope of the disclosure to those skilled in the art. Based on theteachings herein one skilled in the art should appreciate that the scopeof the disclosure is intended to cover any aspect of the disclosuredisclosed herein, whether implemented independently of or combined withany other aspect of the disclosure. For example, an apparatus may beimplemented or a method may be practiced using any number of the aspectsset forth herein. In addition, the scope of the disclosure is intendedto cover such an apparatus or method which is practiced using otherstructure, functionality, or structure and functionality in addition toor other than the various aspects of the disclosure set forth herein. Itshould be understood that any aspect of the disclosure disclosed hereinmay be embodied by one or more elements of a claim.

Several aspects of telecommunication systems will now be presented withreference to various apparatuses and techniques. These apparatuses andtechniques will be described in the following detailed description andillustrated in the accompanying drawings by various blocks, modules,components, circuits, steps, processes, algorithms, and/or the like(collectively referred to as “elements”). These elements may beimplemented using hardware, software, or combinations thereof. Whethersuch elements are implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem.

It should be noted that while aspects may be described herein usingterminology commonly associated with 3G and/or 4G wireless technologies,aspects of the present disclosure can be applied in othergeneration-based communication systems, such as 5G and later, includingNR technologies.

FIG. 1 is a diagram illustrating a wireless network 100 in which aspectsof the present disclosure may be practiced. The wireless network 100 maybe an LTE network or some other wireless network, such as a 5G or NRnetwork. The wireless network 100 may include a number of BSs 110 (shownas BS 110 a, BS 110 b, BS 110 c, and BS 110 d) and other networkentities. A BS is an entity that communicates with user equipment (UEs)and may also be referred to as a base station, a NR BS, a Node B, a gNB,a 5G node B (NB), an access point, a transmit receive point (TRP),and/or the like. Each BS may provide communication coverage for aparticular geographic area. In 3GPP, the term “cell” can refer to acoverage area of a BS and/or a BS subsystem serving this coverage area,depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, afemto cell, and/or another type of cell. A macro cell may cover arelatively large geographic area (e.g., several kilometers in radius)and may allow unrestricted access by UEs with service subscription. Apico cell may cover a relatively small geographic area and may allowunrestricted access by UEs with service subscription. A femto cell maycover a relatively small geographic area (e.g., a home) and may allowrestricted access by UEs having association with the femto cell (e.g.,UEs in a closed subscriber group (CSG)). A BS for a macro cell may bereferred to as a macro BS. A BS for a pico cell may be referred to as apico BS. A BS for a femto cell may be referred to as a femto BS or ahome BS. In the example shown in FIG. 1 , a BS 110 a may be a macro BSfor a macro cell 102 a, a BS 110 b may be a pico BS for a pico cell 102b, and a BS 110 c may be a femto BS for a femto cell 102 c. A BS maysupport one or multiple (e.g., three) cells. The terms “eNB”, “basestation”, “NR BS”, “gNB”, “TRP”, “AP”, “node B”, “5G NB”, and “cell” maybe used interchangeably herein.

In some aspects, a cell may not necessarily be stationary, and thegeographic area of the cell may move according to the location of amobile BS. In some aspects, the BSs may be interconnected to one anotherand/or to one or more other BSs or network nodes (not shown) in thewireless network 100 through various types of backhaul interfaces suchas a direct physical connection, a virtual network, and/or the likeusing any suitable transport network.

Wireless network 100 may also include relay stations. A relay station isan entity that can receive a transmission of data from an upstreamstation (e.g., a BS or a UE) and send a transmission of the data to adownstream station (e.g., a UE or a BS). A relay station may also be aUE that can relay transmissions for other UEs. In the example shown inFIG. 1 , a relay station 110 d may communicate with macro BS 110 a and aUE 120 d in order to facilitate communication between BS 110 a and UE120 d. A relay station may also be referred to as a relay BS, a relaybase station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs ofdifferent types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/orthe like. These different types of BSs may have different transmit powerlevels, different coverage areas, and different impacts on interferencein wireless network 100. For example, macro BSs may have a high transmitpower level (e.g., 5 to 40 Watts) whereas pico BSs, femto BSs, and relayBSs may have lower transmit power levels (e.g., 0.1 to 2 Watts).

A network controller 130 may couple to a set of BSs and may providecoordination and control for these BSs. Network controller 130 maycommunicate with the BSs via a backhaul. The BSs may also communicatewith one another, e.g., directly or indirectly via a wireless orwireline backhaul.

UEs 120 (e.g., 120 a, 120 b, 120 c) may be dispersed throughout wirelessnetwork 100, and each UE may be stationary or mobile. A UE may also bereferred to as an access terminal, a terminal, a mobile station, asubscriber unit, a station, and/or the like. A UE may be a cellularphone (e.g., a smart phone), a personal digital assistant (PDA), awireless modem, a wireless communication device, a handheld device, alaptop computer, a cordless phone, a wireless local loop (WLL) station,a tablet, a camera, a gaming device, a netbook, a smartbook, anultrabook, a medical device or equipment, biometric sensors/devices,wearable devices (smart watches, smart clothing, smart glasses, smartwrist bands, smart jewelry (e.g., smart ring, smart bracelet)), anentertainment device (e.g., a music or video device, or a satelliteradio), a vehicular component or sensor, smart meters/sensors,industrial manufacturing equipment, a global positioning system device,or any other suitable device that is configured to communicate via awireless or wired medium.

Some UEs may be considered machine-type communication (MTC) or evolvedor enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEsinclude, for example, robots, drones, remote devices, sensors, meters,monitors, location tags, and/or the like, that may communicate with abase station, another device (e.g., remote device), or some otherentity. A wireless node may provide, for example, connectivity for or toa network (e.g., a wide area network such as Internet or a cellularnetwork) via a wired or wireless communication link. Some UEs may beconsidered Internet-of-Things (IoT) devices, and/or may be implementedas NB-IoT (narrowband internet of things) devices. Some UEs may beconsidered a Customer Premises Equipment (CPE). UE 120 may be includedinside a housing that houses components of UE 120, such as processorcomponents, memory components, and/or the like.

In general, any number of wireless networks may be deployed in a givengeographic area. Each wireless network may support a particular RAT andmay operate on one or more frequencies. A RAT may also be referred to asa radio technology, an air interface, and/or the like. A frequency mayalso be referred to as a carrier, a frequency channel, and/or the like.Each frequency may support a single RAT in a given geographic area inorder to avoid interference between wireless networks of different RATs.In some cases, NR or 5G RAT networks may be deployed.

In some aspects, two or more UEs 120 (e.g., shown as UE 120 a and UE 120e) may communicate directly using one or more sidelink channels (e.g.,without using a base station 110 as an intermediary to communicate withone another). For example, the UEs 120 may communicate usingpeer-to-peer (P2P) communications, device-to-device (D2D)communications, a vehicle-to-everything (V2X) protocol (e.g., which mayinclude a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure(V2I) protocol, and/or the like), a mesh network, and/or the like. Inthis case, the UE 120 may perform scheduling operations, resourceselection operations, and/or other operations described elsewhere hereinas being performed by the base station 110.

As indicated above, FIG. 1 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 1 .

FIG. 2 shows a block diagram of a design 200 of base station 110 and UE120, which may be one of the base stations and one of the UEs in FIG. 1. Base station 110 may be equipped with T antennas 234 a through 234 t,and UE 120 may be equipped with R antennas 252 a through 252 r, where ingeneral T≥1 and R≥1.

At base station 110, a transmit processor 220 may receive data from adata source 212 for one or more UEs, select one or more modulation andcoding schemes (MCS) for each UE based at least in part on channelquality indicators (CQIs) received from the UE, process (e.g., encodeand modulate) the data for each UE based at least in part on the MCS(s)selected for the UE, and provide data symbols for all UEs. Transmitprocessor 220 may also process system information (e.g., for semi-staticresource partitioning information (SRPI) and/or the like) and controlinformation (e.g., CQI requests, grants, upper layer signaling, and/orthe like) and provide overhead symbols and control symbols. Transmitprocessor 220 may also generate reference symbols for reference signals(e.g., the cell-specific reference signal (CRS)) and synchronizationsignals (e.g., the primary synchronization signal (PSS) and secondarysynchronization signal (SSS)). A transmit (TX) multiple-inputmultiple-output (MIMO) processor 230 may perform spatial processing(e.g., precoding) on the data symbols, the control symbols, the overheadsymbols, and/or the reference symbols, if applicable, and may provide Toutput symbol streams to T modulators (MODs) 232 a through 232 t. Eachmodulator 232 may process a respective output symbol stream (e.g., forOFDM and/or the like) to obtain an output sample stream. Each modulator232 may further process (e.g., convert to analog, amplify, filter, andupconvert) the output sample stream to obtain a downlink signal. Tdownlink signals from modulators 232 a through 232 t may be transmittedvia T antennas 234 a through 234 t, respectively. According to variousaspects described in more detail below, the synchronization signals canbe generated with location encoding to convey additional information.

At UE 120, antennas 252 a through 252 r may receive the downlink signalsfrom base station 110 and/or other base stations and may providereceived signals to demodulators (DEMODs) 254 a through 254 r,respectively. Each demodulator 254 may condition (e.g., filter, amplify,downconvert, and digitize) a received signal to obtain input samples.Each demodulator 254 may further process the input samples (e.g., forOFDM and/or the like) to obtain received symbols. A MIMO detector 256may obtain received symbols from all R demodulators 254 a through 254 r,perform MIMO detection on the received symbols if applicable, andprovide detected symbols. A receive processor 258 may process (e.g.,demodulate and decode) the detected symbols, provide decoded data for UE120 to a data sink 260, and provide decoded control information andsystem information to a controller/processor 280. A channel processormay determine reference signal received power (RSRP), received signalstrength indicator (RSSI), reference signal received quality (RSRQ),channel quality indicator (CQI), and/or the like. In some aspects, oneor more components of UE 120 may be included in a housing.

On the uplink, at UE 120, a transmit processor 264 may receive andprocess data from a data source 262 and control information (e.g., forreports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) fromcontroller/processor 280. Transmit processor 264 may also generatereference symbols for one or more reference signals. The symbols fromtransmit processor 264 may be precoded by a TX MIMO processor 266 ifapplicable, further processed by modulators 254 a through 254 r (e.g.,for DFT-s-OFDM, CP-OFDM, and/or the like), and transmitted to basestation 110. At base station 110, the uplink signals from UE 120 andother UEs may be received by antennas 234, processed by demodulators232, detected by a MIMO detector 236 if applicable, and furtherprocessed by a receive processor 238 to obtain decoded data and controlinformation sent by UE 120. Receive processor 238 may provide thedecoded data to a data sink 239 and the decoded control information tocontroller/processor 240. Base station 110 may include communicationunit 244 and communicate to network controller 130 via communicationunit 244. Network controller 130 may include communication unit 294,controller/processor 290, and memory 292.

Controller/processor 240 of base station 110, controller/processor 280of UE 120, and/or any other component(s) of FIG. 2 may perform one ormore techniques for a random access response for a two-step randomaccess procedure, as described in more detail elsewhere herein. Forexample, controller/processor 240 of base station 110,controller/processor 280 of UE 120, and/or any other component(s) ofFIG. 2 may perform or direct operations of, for example, process 400 ofFIG. 4 , process 500 of FIG. 5 , and/or other processes as describedherein. Memories 242 and 282 may store data and program codes for basestation 110 and UE 120, respectively. A scheduler 246 may schedule UEsfor data transmission on the downlink and/or uplink.

In some aspects, base station 110 may include means for detecting apreamble of a random access message associated with a two-step randomaccess procedure, wherein the random access message is received from UE120; means for processing a payload of the random access message,wherein an outcome of processing the payload is either successfullydecoding the payload or failing to decode the payload; and means fortransmitting, based at least in part on detecting the preamble and theoutcome of processing the payload, a random access response associatedwith the two-step random access procedure, wherein the random accessresponse includes an uplink group grant, and an indication of a type ofthe uplink group grant, for a plurality of UEs including UE 120, whereinpreamble transmissions of the plurality of UEs share a time andfrequency occasion; and/or the like. In some aspects, such means mayinclude one or more components of base station 110 described inconnection with FIG. 2 .

In some aspects, a base station 110 may include means for constructingan uplink group grant for a plurality of UEs 120 performing a two-steprandom access procedure, wherein preambles or payloads of random accessmessages provided by the plurality of UEs 120 have been detected by thebase station; means for transmitting a random access response associatedwith the two-step random access procedure, wherein the random accessresponse includes the uplink group grant and an indication of a type ofthe uplink group grant; and/or the like. In some aspects, such means mayinclude one or more components of base station 110 described inconnection with FIG. 2 .

In some aspects, UE 120 may include means for transmitting a preambleand a payload of a random access message associated with a two-steprandom access procedure; means for receiving a random access response,associated with the two-step random access procedure, including anuplink group grant and an indication of a type of the uplink group grantfor a plurality of UEs including UE 120; means for transmitting anuplink communication on a set of shared time-frequency resources basedat least in part on the uplink group grant; and/or the like. In someaspects, such means may include one or more components of UE 120described in connection with FIG. 2 .

In some aspects, a UE 120 may include means for transmitting a preambleand a payload of a random access message associated with a two-steprandom access procedure; means for receiving a random access responseassociated with the two-step random access procedure after transmittingthe preamble and the payload of the random access message, wherein therandom access response includes an uplink group grant for a plurality ofUEs including the UE, and wherein the random access response includes anindication of a type of the uplink group grant; and/or the like. In someaspects, such means may include one or more components of UE 120described in connection with FIG. 2 .

As indicated above, FIG. 2 is provided as an example. Other examples maydiffer from what is described with regard to FIG. 2 .

A two-step random access channel (RACH) procedure includes two steps(rather than four steps, as in a traditional four-step RACH procedure).In the two-step RACH procedure, a UE transmits a random access message(referred to as msgA) that includes a (e.g., randomly selected) preambleand a payload (e.g., a physical uplink shared channel (PUSCH) payload).In an ideal case, a base station successfully detects the preamble andsuccessfully decodes the payload, and transmits a random access response(referred to as msgB) to the UE. The random access response includes aphysical downlink control channel (PDCCH) communication and a physicaldownlink shared channel (PDSCH) payload, where the PDCCH communicationidentifies resources of the PDSCH payload that carry information for theUE. The PDSCH payload can include, for example, contention resolutioninformation for the UE, a cell radio network temporary identifier(C-RNTI) for the UE, a timing advance (TA) command for the UE, and/orthe like. The random access response associated with the two-step RACHprocedure in this ideal case (i.e., when the base station detects themsgA preamble and decodes the msgA payload) is referred to herein as asuccess random access response (SuccessRAR).

In some cases, however, the base station may not detect the preamble ofthe random access message and/or may fail to decode the payload of therandom access message. Such a situation may arise due to, for example,channel impairments, contention-based multiple access, and/or the like.Thus, in order to improve reliability of the two-step RACH procedure,fallback to a transmission of another random access message (e.g., amessage similar to msg3 in the traditional four-step RACH procedure)and/or retransmission of the random access message (e.g., retransmissionof msgA) may be supported.

In a case in which the base station successfully detects the preamble ofthe random access message but fails to decode the payload of the randomaccess message, the base station may send a random access responseincluding a random access preamble identifier (RAPID) associated withthe detected preamble, an uplink grant for the UE, a TA command for theUE, and a temporary C-RNTI (TC-RNTI) for the UE. The random accessresponse associated with the two-step RACH procedure in the case wherethe preamble is detected but the payload is not successfully decoded isherein referred to as a fallback random access response (FallbackRAR).Generally, when a UE performing the two-step RACH procedure receives afallback random access response, the UE falls back to the four-step RACHprocedure and, based on receiving the fallback random access response,transmits another random access message (e.g., msg3). Here, the contentsof the other random access message can be similar to or different fromthat of the payload of the random access message transmitted by the UEduring the two-step RACH attempt. Notably, the UE need not transmit thepreamble with the other random access message since the base station hasalready detected the preamble. In a case in which the base station doesnot detect the preamble of the random access message, the base stationmay send back-off indication information in a random access responsemedium access control (MAC) sub-header (e.g., such that the UE canretransmit the random access message at a later time).

As indicated above, in the conventional two-step RACH procedure, thebase station includes an uplink grant for a UE (e.g., a single UE uplinkgrant) in a given fallback random access response, but does not includeany uplink grant in a success random access response. This uplink grantdesign for two-step RACH may cause inefficiencies in terms of, forexample, spectral efficiency, power consumption, and signaling overhead.

Some aspects described herein provide uplink grant design improvementsfor the two-step RACH procedure. For example, in some aspects, theuplink grant included in a fallback random access response may be anuplink group grant for a plurality of UEs (e.g., in order to allow theplurality of UEs to share uplink resources for further uplinktransmissions). As another example, in some aspects, an uplink grant maybe included in a success random access response (e.g., in order to allowa UE to send additional uplink data without a need to request uplinkresources). Here, the uplink grant can be a single-UE grant or can be anuplink group grant for a plurality of UEs. As still another example, anuplink group grant can be used by UEs for which different random accessmessage processing outcomes were reached (e.g., a UE for which decodingof a payload of a msgA failed and a second UE for which decoding of apayload of a msgA succeeded, where the second UE needs to transmitadditional uplink data). As described below, the uplink grant designaspects described herein provide higher spectral efficiency and reducepower consumption, while reducing signaling overhead.

FIGS. 3A-3C are diagrams illustrating examples associated with a randomaccess response for a two-step random access procedure, in accordancewith various aspects of the present disclosure. For the purposes of theexamples shown in FIGS. 3A-3C, a UE (e.g., UE 120) is configured to usea two-step RACH procedure in association with connecting to a basestation (e.g., base station 110).

FIG. 3A is a diagram of an example 300 in which an uplink grant includedin a fallback random access response is an uplink group grant associatedwith a plurality of UEs including the UE. As shown in FIG. 3A, and byreference numbers 302 and 304, the UE may transmit a preamble of arandom access message associated with the two-step RACH procedure (msgAPreamble) and a payload of the random access message associated with thetwo-step RACH procedure (msgA Payload).

As shown by reference number 306, the base station detects the preambleof the random access message. However, as shown by reference number 308,the base station fails to decode the payload of the random accessmessage.

As shown by reference number 310, based at least in part on detectingthe preamble and failing to decode the payload, the base station maytransmit a random access response, associated with the two-step randomaccess procedure, that includes an uplink group grant for a plurality ofUEs including the UE. In other words, the base station may transmit amsgB with a fallback random access response that includes an uplinkgroup grant. In some aspects, the fallback random access response mayinclude a set of K (K≥1) RAPIDs, each associated with a respective oneof K UEs for which preambles were detected, but payloads were notsuccessfully decoded.

The uplink group grant is an uplink grant for a plurality of UEs,meaning that the plurality of UEs may share resources of the uplinkgrant in association with additional uplink transmissions. In someaspects, the uplink group grant may indicate a set of resources and amodulation and coding scheme (MCS) to be used by the plurality of UEsfor transmitting other random access messages (e.g., a set of resourcesand an MCS to be used by the UEs for transmitting a msg3).

In some aspects, a demodulation reference signal (DMRS) resourceconfiguration (e.g., port and/or sequences) for the plurality of UEs maybe explicitly indicated in the uplink group grant. Alternatively, a DMRSresource configuration for the plurality of UEs may be implicitlyindicated by a mapping rule associated with preamble resource indicesand DMRS resource indices configured for the plurality of UEs by thebase station (e.g., a mapping rule between a preamble resource index anda DMRS resource index, wherein the preamble resource indexing caninclude both RACH occasions (ROs) and sequences, and the DMRS resourceindexing can include both antenna ports and sequences).

In some aspects, the base station may transmit a timing advance (TA)command, associated with the UE, and a temporary cell radio networktemporary identifier (TC-RNTI), associated with the UE, separately fromthe uplink group grant (e.g., such that each of the plurality of UEs canreceive a respective TA command and TC-RNTI).

In some aspects, the uplink group grant may be the only uplink groupgrant included in the random access response. In other words, in somecases, the random access response transmitted by the base station mayinclude a single uplink group grant for the plurality of UEs.

Alternatively, in some aspects, the random access response may includemultiple uplink group grants. For example, the uplink group grant may bea first uplink group grant and the plurality of UEs may be a firstplurality of UEs for which preambles were detected but payloads were notsuccessfully decoded. In this example, the random access response mayfurther include a second uplink group grant associated with a secondplurality of UEs (e.g., a separate uplink group grant for anotherplurality of UEs for which preambles were detected but payloads were notsuccessfully decoded). In some aspects, the base station may partition agroup of UEs into the first plurality of UEs and the second plurality ofUEs based at least in part on, for example, proximities of timingoffsets associated with the group of UEs or UE statuses associated withthe group of UEs (e.g., derived from rules for msgA preamble, ROselection, and/or the like).

In some aspects, the random access response may further include asingle-UE uplink grant for another UE. For example, the random accessresponse may include the uplink group grant for the plurality of UEs,and may further include a single-UE grant for another UE (e.g., a UE notincluded in the plurality of UEs).

As further shown in FIG. 3A, and by reference number 312, the UE mayreceive the random access response including the uplink group grant forthe plurality of UEs, and may transmit an uplink communication (e.g.,msg3) based at least in part on the uplink group grant. Here, the UE mayindividually adjust the timing offset (e.g., based on the TA commandassociated with the UE) and individually scramble PUSCH bits, but mayuse the set of resources and MCS indicated by the uplink group grant(i.e., the same set of resources and the same MC S as used by other UEsof the plurality of UEs).

Here, use of the uplink group grant improves spectral efficiency sincemultiple UEs can use the same set of resources and MCS in associationwith transmitting uplink communications during the two-step RACHprocedure. Moreover, through use of an uplink group grant (rather thanmultiple single-UE grants) power consumption is decreased at the basestation and signaling overhead is reduced.

FIG. 3B is a diagram of an example 320 in which an uplink grant isincluded in a success random access response. As shown in FIG. 3B, andby reference numbers 322 and 324, the UE may transmit a preamble of arandom access message associated with the two-step RACH procedure (msgAPreamble) and a payload of the random access message associated with thetwo-step RACH procedure (msgA Payload). As indicated by reference number324, the payload of the random access message may include an indicationthat the UE needs to transmit additional uplink data (e.g., that the UEhas uplink data ready for transmission in addition to the uplink dataincluded in the payload). In some aspects, the indication may in theform of a buffer status report (BSR) included in the payload of therandom access message, a scheduling request (SR) included in the payloadof the random access message, and/or the like.

As shown by reference number 326, the base station detects the preambleof the random access message. As shown by reference number 328, the basestation decodes the payload of the random access message. As furthershown by reference number 328, the base station may determine that theUE needs to transmit the additional uplink data. In some aspects, thebase station may determine that the UE needs to transmit additionaluplink data based at least in part on the indication in the payload ofthe random access message.

As shown by reference number 330, based at least in part on determiningthat the UE needs to transmit additional uplink data, the base stationmay transmit a random access response, associated with the two-steprandom access procedure, that includes an uplink grant for the UE. Inother words, the base station may transmit a success random accessresponse that includes an uplink grant.

In some aspects, the uplink grant may be a single-UE uplink grant forthe UE (e.g., an uplink grant specific to the UE). In such a case, insome aspects, the random access response may further include an uplinkgroup grant for a plurality of UEs other than the UE (e.g., a pluralityof other UEs for which payload decoding was successful, where each ofthe plurality of UEs needs to transmit additional uplink data).

In some aspects, the uplink grant may be an uplink group grant for aplurality of UEs including the UE (e.g., a plurality of UEs for whichpayload decoding was successful, where each of the plurality of UEsneeds to transmit additional uplink data). In some aspects, the groupingof the plurality of UEs may be based at least in part on a referencesignal received power (RSRP) measurement, a channel state information(CSI) report, beam management, quality of service (QoS) handling, apositioning-related measurement; and/or the like. In other words, insome aspects, the base station may group UEs to be associated with agiven uplink group grant based at least in part on one or moremeasurements and/or characteristics ascertained from payloads of randomaccess messages transmitted by each of the UEs. The information carriedand/or indicated by the uplink group grant is similar to that describedabove in association with FIG. 3A. In some aspects, the uplink groupgrant may be the only uplink group grant included in the random accessresponse, or may be one of a plurality of uplink group grants includedin the random access response. Further, in a case in which the uplinkgrant is an uplink group grant, the random access response may furtherinclude a single-UE uplink grant for another UE, in some aspects.

As further shown in FIG. 3B, and by reference number 332, the UE mayreceive the random access response including the uplink grant for theUE, and may transmit an uplink communication (e.g., including theadditional uplink data) based at least in part on the uplink grant.Here, if the uplink grant is an uplink group grant, the UE mayindividually adjust the timing offset (e.g., based on a TA commandassociated with the UE) and scramble PUSCH bits, but may use the set ofresources and MCS indicated by the uplink group grant (i.e., the sameset of resources and the same MCS as used by other UEs of the pluralityof UEs).

Here, use of the uplink grant in the success random access response canimprove spectral efficiency since multiple UEs may use the same set ofresources and MCS in association with transmitting uplinkcommunications. Further, by providing the uplink grant in the successrandom access response (rather than waiting for the UE to provide anexplicit request for uplink resources), power consumption is decreasedat the UE and the base station, and signaling overhead is reduced.

FIG. 3C is a diagram of an example 340 in which an uplink grant includedin a fallback random access response is an uplink group grant associatedwith a plurality of UEs including a UE for which decoding of a payloadof a random access message failed and a UE for which decoding of apayload of a random access message succeeded.

In some aspects, the base station may identify a plurality of UEs towhich an uplink group grant is to be transmitted in association with atwo-step random access procedure, where the plurality of UEs includes afirst UE for which decoding of a payload of a first random accessmessage failed, and a second UE for which decoding of a payload of asecond random access message succeeded.

For example, as shown by reference numbers 342 and 344, the first UE(UE1) may transmit a preamble of a first random access message and apayload of the first random access message. As shown by reference number346, the base station detects the preamble of the first random accessmessage. However, as shown by reference number 348, the base stationfails to decode the payload of the first random access message. Further,as shown by reference numbers 350 and 352, the second UE (UE2) maytransmit a preamble of a second random access message and a payload ofthe second random access message. As shown by reference number 354, thebase station detects the preamble of the second random access messageand, as shown by reference number 356, successfully decodes the payloadof the second random access message. In this example, the base stationhas identified a plurality of UEs to which an uplink group grant is tobe transmitted in association with a two-step random access procedure,where the plurality of UEs includes the first UE (e.g., UE1 for whichdecoding of the payload of the first random access message failed), andthe second UE (e.g., UE2 for which decoding of the payload of the secondrandom access message succeeded).

As shown by reference number 358, based at least in part on identifyingthe plurality of UEs, the base station may transmit a random accessresponse, associated with the two-step random access procedure, thatincludes an uplink group grant for a plurality of UEs including thefirst UE and the second UE. Notably, in this case, the uplink groupgrant is to be shared by the plurality of UEs with different msgAprocessing outcomes. In other words, the uplink group grant can beshared by the first UE, for which payload decoding failed (e.g., inorder to transmit msg3), and the second UE, for which payload decodingsucceeded (e.g., in order to transmit an additional uplinkcommunication). Here, a single uplink group grant is needed, rather thanseparate uplink grants being needed in a fallback random access responseand a success random access response.

In some aspects, the base station may transmit, and the plurality of UEsmay receive, the random access response in a set of resourcesindependent from resources corresponding to a fallback random accessresponse and resources corresponding to a success random accessresponse. Alternatively, in some aspects, the base station may transmit,and the plurality of UEs may receive, the uplink group grant in a set ofresources shared by a fallback random access response and a successrandom access response.

In some aspects, the information carried and/or indicated by the uplinkgroup grant may be similar to that described above in association withFIG. 3A. In some aspects, the uplink group grant may be the only uplinkgroup grant included in the random access response, or may be one of aplurality of uplink group grants included in the random access response.Further, in some aspects, the random access response may further includea single-UE uplink grant for another UE.

Similar to the manner described above, the first UE and the second UEmay receive the random access response including the uplink group grant,and may transmit respective uplink communications (e.g., including msg3and the additional uplink data, respectively) based at least in part onthe uplink group grant.

Here, use of the uplink group grant improves spectral efficiency sincemultiple UEs can use the same set of resources and MCS in associationwith transmitting uplink communications during the two-step RACHprocedure. Moreover, through use of an uplink group grant (rather thanmultiple single-UE grants) power consumption is decreased at the basestation and signaling overhead is reduced. Further, by providing theuplink group grant in the random access response to UEs for whichpayload decoding is successful (rather than waiting for the UE toprovide an explicit request for uplink resources), power consumption isdecreased at the UE and the base station, and signaling overhead isreduced.

As indicated in the above examples, the base station may construct oneor more uplink group grants for two-step RACH UEs whose preamble orpayload have been detected. In some aspects, a status of an uplink groupgrant included in the random access response (e.g., msgB) may includeinformation that identifies a number of group grants, information thatidentifies a type of the group grants, an indication of the type of agroup grant, and/or the like. In some aspects, the indication of thetype of the group grant may be based at least in part on a bitmap.

In some aspects, the random access response may include a random accessresponse PDCCH (e.g., a msgB PDCCH) and a random access response PDSCH(e.g., a msgB PDSHC) (including a DMRS).

The random access response PDCCH may include downlink controlinformation (DCI) with a cyclic redundancy check (CRC) attachment, insome aspects. In some aspects, the CRC may be masked with a group RNTI,such as a RA-RNTI. In some aspects, the random access response PDCCH canbe configured within a common search space that is to be monitored by agroup of two-step RACH UEs sharing the same RACH occasion for randomaccess message (e.g., msgA) transmission. In some aspects, the DCI maycarry the resource assignment for the random access response PDSCH. Insome aspects, the DCI may carry an early indication for a type of theuplink group grant, such as an uplink group grant in a FallbackRAR, anuplink group grant in a SuccessRAR, a shared uplink group grant, or thelike.

In some aspects, the random access response PDSCH may include a MACpacket data unit (PDU). In some aspects, the MAC PDU can carry at leasta FallbackRAR and a SuccessRAR, where an uplink group grant can beincluded in the FallbackRAR, the SuccessRAR, or one or more other fieldsof the MAC PDU. In some aspects, an uplink group grant field may includeat least a common time-frequency resource allocation for subsequentuplink transmissions (e.g., PUSCH transmissions). In some aspects, theuplink group grant field also include a MCS, a PUSCH hopping flag, aDMRS resource configuration, and/or a common information for powercontrol and beam management.

As indicated above, FIGS. 3A-3C are provided as examples. Other examplesmay differ from what is described with respect to FIGS. 3A-3C

FIG. 4 is a diagram illustrating an example process 400 performed, forexample, by a base station, in accordance with various aspects of thepresent disclosure. Example process 400 is an example where a basestation (e.g., base station 110 and/or the like) performs operationsassociated with a random access response for a two-step RACH procedure.

As shown in FIG. 4 , in some aspects, process 400 may include detectinga preamble of a random access message associated with a two-step randomaccess procedure (block 410). For example, the base station (e.g., usingreceive processor 238, controller/processor 240, memory 242, and/or thelike) may detect a preamble of a random access message associated with atwo-step random access procedure, as described above. In some aspects,the random access message is received from a UE (e.g., UE 120).

As further shown in FIG. 4 , in some aspects, process 400 may includeprocessing a payload of the random access message, wherein an outcome ofprocessing the payload is either successfully decoding the payload orfailing to decode the payload (block 420). For example, the base station(e.g., using receive processor 238, controller/processor 240, memory242, and/or the like) may process a payload of the random accessmessage, as described above. In some aspects, an outcome of processingthe payload is either successfully decoding the payload or failing todecode the payload.

As further shown in FIG. 4 , in some aspects, process 400 may includetransmitting, based at least in part on detecting the preamble and theoutcome of processing the payload, a random access response associatedwith the two-step random access procedure, wherein the random accessresponse includes an uplink group grant, and an indication of a type ofthe uplink group grant, for a plurality of UEs including the UE (block430). For example, the base station (e.g., using transmit processor 220,receive processor 238, controller/processor 240, memory 242, and/or thelike) may transmit, based at least in part on detecting the preamble andthe outcome of processing the payload, a random access responseassociated with the two-step random access procedure, as describedabove. In some aspects, the random access response includes an uplinkgroup grant, and an indication of a type of the uplink group grant, fora plurality of UEs including the UE. In some aspects, preambletransmissions of the plurality of UEs share a time and frequencyoccasion.

Process 400 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, when the outcome of processing the payload of therandom access message is failing to decode the payload, the uplink groupgrant is included in the random access response based at least in parton failing to decode the payload.

In a second aspect, alone or in combination with the first aspect, theuplink group grant is included in a fallback random access response.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the UE is included in the plurality of UEs based atleast in part on a timing offset associated with the UE or a UE statusof the UE. For example, a group of UEs can be partitioned into two ormore pluralities of UEs, including the plurality of UEs, based at leastin part on proximities of timing offsets associated with the group ofUEs or UE statuses associated with the group of UEs.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, the uplink group grant indicates a commonset of time-frequency resources, a modulation and coding scheme (MCS),common information for power control or beam management, and a physicaluplink shared channel (PUSCH) hopping flag to be used by the pluralityof UEs for transmitting other random access messages.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, a demodulation reference signal (DMRS) resourceconfiguration for the plurality of UEs is explicitly indicated in theuplink group grant.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, a demodulation reference signal (DMRS) resourceconfiguration for the plurality of UEs is implicitly indicated by amapping rule associated with preamble resource indices and DMRS resourceindices configured for the plurality of UEs by the base station.

In a seventh aspect, alone or in combination with one or more of thefirst through sixth aspects, a timing advance (TA) command, associatedwith the UE, and a temporary cell radio network temporary identifier(TC-RNTI), associated with the UE, are transmitted separately from theuplink group grant.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, the uplink group grant is an only uplinkgroup grant included in the random access response.

In a ninth aspect, alone or in combination with one or more of the firstthrough eighth aspects, the uplink group grant is one of a plurality ofuplink group grants included in the random access response.

In a tenth aspect, alone or in combination with one or more of the firstthrough ninth aspects, the random access response further includes asingle-UE uplink grant for another UE.

In an eleventh aspect, alone or in combination with one or more of thefirst through tenth aspects, the outcome of processing the payload ofthe random access message is successfully decoding the payload. Here thebase station may determine, based at least in part on an indication inthe payload, that the UE needs to transmit additional uplink data.

In a twelfth aspect, alone or in combination with one or more of thefirst through eleventh aspects, the uplink group grant is included in asuccess random access response.

In a thirteenth aspect, alone or in combination with one or more of thefirst through twelfth aspects, the indication is provided via a bufferstatus report (BSR).

In a fourteenth aspect, alone or in combination with one or more of thefirst through thirteenth aspects, the indication is provided via ascheduling request (SR).

In a fifteenth aspect, alone or in combination with one or more of thefirst through fourteenth aspects, the UE is grouped into the pluralityof UEs based at least in part on at least one of: a reference signalreceived power (RSRP) measurement, a channel state information (CSI)report, beam management, quality of service (QoS) handling, or apositioning-related measurement.

In a sixteenth aspect, alone or in combination with one or more of thefirst through fifteenth aspects, the uplink group grant is transmittedin a resource independent from resources corresponding to a fallbackrandom access response and resources corresponding to a success randomaccess response.

In a seventeenth aspect, alone or in combination with one or more of thefirst through sixteenth aspects, the uplink group grant is transmittedin a set of resources shared by a fallback random access response and asuccess random access response.

In an eighteenth aspect, alone or in combination with one or more of thefirst through seventeenth aspects, the indication of the type of theuplink group grant is transmitted in a downlink control information(DCI) field of a random access response physical downlink controlchannel (PDCCH).

In a nineteenth aspect, alone or in combination with one or more of thefirst through eighteenth aspects, the indication of the type of theuplink group grant is based at least in part on a bitmap.

In a twentieth aspect, alone or in combination with one or more of thefirst through nineteenth aspects, the DCI is associated with a cyclicredundancy check (CRC). Here, the CRC may be masked by a group radionetwork temporary identifier (RNTI).

In a twenty first aspect, alone or in combination with one or more ofthe first through twentieth aspects, the random access response PDCCH istransmitted in a common search space.

Although FIG. 4 shows example blocks of process 400, in some aspects,process 400 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 4 .Additionally, or alternatively, two or more of the blocks of process 400may be performed in parallel.

FIG. 5 is a diagram illustrating an example process 500 performed, forexample, by a UE, in accordance with various aspects of the presentdisclosure. Example process 500 is an example where a UE (e.g., UE 120and/or the like) performs operations associated with a random accessresponse for a two-step RACH procedure.

As shown in FIG. 5 , in some aspects, process 500 may includetransmitting a preamble and a payload of a random access messageassociated with a two-step random access procedure (block 510). Forexample, the UE (e.g., using transmit processor 264,controller/processor 280, memory 282, and/or the like) may transmit apreamble and a payload of a random access message associated with atwo-step random access procedure, as described above.

As further shown in FIG. 5 , in some aspects, process 500 may includereceiving a random access response, associated with the two-step randomaccess procedure, including an uplink group grant and an indication of atype of the uplink group grant for a plurality of UEs including the UE(block 520). For example, the UE (e.g., using receive processor 258,controller/processor 280, memory 282, and/or the like) may receive arandom access response, associated with the two-step random accessprocedure, including an uplink group grant and an indication of a typeof the uplink group grant for a plurality of UEs including the UE, asdescribed above.

As further shown in FIG. 5 , in some aspects, process 500 may includetransmitting an uplink communication on a set of shared time-frequencyresources based at least in part on the uplink group grant (block 530).For example, the UE (e.g., using transmit processor 264,controller/processor 280, memory 282, and/or the like) may transmit anuplink communication on a set of shared time-frequency resources basedat least in part on the uplink group grant, as described above.

Process 500 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the uplink group grant is included in the randomaccess response based at least in part on a base station failing todecode the payload.

In a second aspect, alone or in combination with the first aspect, theuplink group grant is included in a fallback random access response.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the UE is included in the plurality of UEs based atleast in part on a timing offset associated with the UE or a UE statusof the UE.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, the uplink group grant indicates a commonset of time-frequency resources, a modulation and coding scheme (MCS),common information for power control or beam management, and a physicaluplink shared channel (PUSCH) hopping flag to be used by the pluralityof UEs for transmitting other random access messages.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, a demodulation reference signal (DMRS) resourceconfiguration for the plurality of UEs is explicitly indicated in theuplink group grant.

In a sixth aspect, alone or in combination with one or more of the firstthrough fifth aspects, a demodulation reference signal (DMRS) resourceconfiguration for the plurality of UEs is implicitly indicated by amapping rule associated with preamble resource indices and DMRS resourceindices configured for the plurality of UEs by the base station.

In a seventh aspect, alone or in combination with one or more of thefirst through sixth aspects, a timing advance (TA) command, associatedwith the UE, and a temporary cell radio network temporary identifier(TC-RNTI), associated with the UE, are received separately from theuplink group grant.

In an eighth aspect, alone or in combination with one or more of thefirst through seventh aspects, the uplink group grant is an only uplinkgroup grant included in the random access response.

In a ninth aspect, alone or in combination with one or more of the firstthrough eighth aspects, the uplink group grant is one of a plurality ofuplink group grants included in the random access response.

In a tenth aspect, alone or in combination with one or more of the firstthrough ninth aspects, the random access response further includes asingle-UE uplink grant for another UE.

In an eleventh aspect, alone or in combination with one or more of thefirst through tenth aspects, an indication that the UE needs to transmitadditional uplink data is included in the payload.

In a twelfth aspect, alone or in combination with one or more of thefirst through eleventh aspects, the uplink group grant is included in asuccess random access response.

In a thirteenth aspect, alone or in combination with one or more of thefirst through twelfth aspects, the indication is provided via a bufferstatus report (BSR).

In a fourteenth aspect, alone or in combination with one or more of thefirst through thirteenth aspects, the indication is provided via ascheduling request (SR).

In a fifteenth aspect, alone or in combination with one or more of thefirst through fourteenth aspects, the UE is grouped into the pluralityof UEs based at least in part on at least one of: a reference signalreceived power (RSRP) measurement, a channel state information (CSI)report, beam management, quality of service (QoS) handling, or apositioning-related measurement.

In a sixteenth aspect, alone or in combination with one or more of thefirst through fifteenth aspects, the uplink group grant is received in aresource independent from resources corresponding to a fallback randomaccess response and resources corresponding to a success random accessresponse.

In a seventeenth aspect, alone or in combination with one or more of thefirst through sixteenth aspects, the uplink group grant is received in aset of resources shared by a fallback random access response and asuccess random access response.

In an eighteenth aspect, alone or in combination with one or more of thefirst through seventeenth aspects, the indication of the type of theuplink group grant is received in a downlink control information (DCI)field of a random access response physical downlink control channel(PDCCH) based at least in part on monitoring the random access responsePDCCH.

In a nineteenth aspect, alone or in combination with one or more of thefirst through eighteenth aspects, the DCI is associated with a cyclicredundancy check (CRC). Here, the CRC may be de-masked with a groupradio network temporary identifier (RNTI).

In a twentieth aspect, alone or in combination with one or more of thefirst through nineteenth aspects, the DCI is decoded to determine aresource assignment of a random access response physical downlink sharedchannel (PDSCH). Here, the indication of the type of the uplink groupgrant may be carried in the random access response PDSCH.

In a twenty first aspect, alone or in combination with one or more ofthe first through twentieth aspects, the random access response and theuplink group grant are decoded.

In a twenty second aspect, alone or in combination with one or more ofthe first through twenty first aspects, a timing advance (TA), amodulation and coding scheme (MCS), power control, beam management, andtime-frequency resource allocation is applied in association withtransmitting the uplink communication.

Although FIG. 5 shows example blocks of process 500, in some aspects,process 500 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 5 .Additionally, or alternatively, two or more of the blocks of process 500may be performed in parallel.

FIG. 6 is a diagram illustrating an example process 600 performed, forexample, by a base station, in accordance with various aspects of thepresent disclosure. Example process 600 is an example where the basestation (e.g., base station 110 and/or the like) performs operationsassociated with design considerations for a random access response for atwo-step random access procedure.

As shown in FIG. 6 , in some aspects, process 600 may includeconstructing an uplink group grant for a plurality of UEs performing atwo-step random access procedure, wherein preambles or payloads ofrandom access messages provided by the plurality of UEs have beendetected by the base station (block 610). For example, the base station(e.g., using transmit processor 220, receive processor 238,controller/processor 240, memory 242, and/or the like) may construct anuplink group grant for a plurality of UEs (e.g., UEs 120) performing atwo-step random access procedure, as described above. In some aspects,preambles or payloads of random access messages provided by theplurality of UEs have been detected by the base station.

As further shown in FIG. 6 , in some aspects, process 600 may includetransmitting a random access response associated with the two-steprandom access procedure, wherein the random access response includes theuplink group grant and an indication of a type of the uplink group grant(block 620). For example, the base station (e.g., using transmitprocessor 220, controller/processor 240, memory 242, and/or the like)may transmit a random access response associated with the two-steprandom access procedure, as described above. In some aspects, the randomaccess response includes the uplink group grant and an indication of atype of the uplink group grant.

Process 600 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the random access response includes a status of theuplink group grant, the status including at least one of informationthat identifies a number of uplink group grants included in the randomaccess response, or the indication of the type of the uplink groupgrant.

In a second aspect, alone or in combination with the first aspect, theindication of the type of the uplink group grant is transmitted in a DCIfield of a random access response PDCCH.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the indication of the type of the uplink group grantis based at least in part on a bitmap.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, wherein the DCI is associated with a CRC,wherein the CRC is masked by a group RNTI.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, the random access response PDCCH is transmittedin a common search space.

Although FIG. 6 shows example blocks of process 600, in some aspects,process 600 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 6 .Additionally, or alternatively, two or more of the blocks of process 600may be performed in parallel.

FIG. 7 is a diagram illustrating an example process 700 performed, forexample, by a UE, in accordance with various aspects of the presentdisclosure. Example process 700 is an example where the UE (e.g., UE 120and/or the like) performs operations associated with designconsiderations for a random access response for a two-step random accessprocedure.

As shown in FIG. 7 , in some aspects, process 700 may includetransmitting a preamble and a payload of a random access messageassociated with a two-step random access procedure (block 710). Forexample, the UE (e.g., using transmit processor 264,controller/processor 280, memory 282, and/or the like) may transmit apreamble and a payload of a random access message associated with atwo-step random access procedure, as described above.

As further shown in FIG. 7 , in some aspects, process 700 may includereceiving a random access response associated with the two-step randomaccess procedure after transmitting the preamble and the payload of therandom access message, wherein the random access response includes anuplink group grant for a plurality of UEs including the UE, and whereinthe random access response includes an indication of a type of theuplink group grant (block 720). For example, the UE (e.g., using receiveprocessor 258, controller/processor 280, memory 282, and/or the like)may receive a random access response associated with the two-step randomaccess procedure after transmitting the preamble and the payload of therandom access message, as described above. In some aspects, the randomaccess response includes an uplink group grant for a plurality of UEsincluding the UE, and wherein the random access response includes anindication of a type of the uplink group grant.

Process 700 may include additional aspects, such as any single aspect orany combination of aspects described below and/or in connection with oneor more other processes described elsewhere herein.

In a first aspect, the random access response includes a status of theuplink group grant, the status including at least one of informationthat identifies a number of uplink group grants included in the randomaccess response, or the indication of the type of the uplink groupgrant.

In a second aspect, alone or in combination with the first aspect, theindication of the type of the uplink group grant is received in a DCIfield of a random access response PDCCH.

In a third aspect, alone or in combination with one or more of the firstand second aspects, the indication of the type of the uplink group grantis based at least in part on a bitmap.

In a fourth aspect, alone or in combination with one or more of thefirst through third aspects, wherein the DCI is associated with a CRC,wherein the CRC is masked by a group RNTI.

In a fifth aspect, alone or in combination with one or more of the firstthrough fourth aspects, the random access response PDCCH is received ina common search space.

Although FIG. 7 shows example blocks of process 700, in some aspects,process 700 may include additional blocks, fewer blocks, differentblocks, or differently arranged blocks than those depicted in FIG. 7 .Additionally, or alternatively, two or more of the blocks of process 700may be performed in parallel.

The foregoing disclosure provides illustration and description, but isnot intended to be exhaustive or to limit the aspects to the preciseform disclosed. Modifications and variations may be made in light of theabove disclosure or may be acquired from practice of the aspects.

As used herein, the term “component” is intended to be broadly construedas hardware, firmware, and/or a combination of hardware and software. Asused herein, a processor is implemented in hardware, firmware, and/or acombination of hardware and software.

As used herein, satisfying a threshold may, depending on the context,refer to a value being greater than the threshold, greater than or equalto the threshold, less than the threshold, less than or equal to thethreshold, equal to the threshold, not equal to the threshold, and/orthe like.

It will be apparent that systems and/or methods described herein may beimplemented in different forms of hardware, firmware, and/or acombination of hardware and software. The actual specialized controlhardware or software code used to implement these systems and/or methodsis not limiting of the aspects. Thus, the operation and behavior of thesystems and/or methods were described herein without reference tospecific software code—it being understood that software and hardwarecan be designed to implement the systems and/or methods based, at leastin part, on the description herein.

Even though particular combinations of features are recited in theclaims and/or disclosed in the specification, these combinations are notintended to limit the disclosure of various aspects. In fact, many ofthese features may be combined in ways not specifically recited in theclaims and/or disclosed in the specification. Although each dependentclaim listed below may directly depend on only one claim, the disclosureof various aspects includes each dependent claim in combination withevery other claim in the claim set. A phrase referring to “at least oneof” a list of items refers to any combination of those items, includingsingle members. As an example, “at least one of: a, b, or c” is intendedto cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combinationwith multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c,a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering ofa, b, and c).

No element, act, or instruction used herein should be construed ascritical or essential unless explicitly described as such. Also, as usedherein, the articles “a” and “an” are intended to include one or moreitems, and may be used interchangeably with “one or more.” Furthermore,as used herein, the terms “set” and “group” are intended to include oneor more items (e.g., related items, unrelated items, a combination ofrelated and unrelated items, and/or the like), and may be usedinterchangeably with “one or more.” Where only one item is intended, thephrase “only one” or similar language is used. Also, as used herein, theterms “has,” “have,” “having,” and/or the like are intended to beopen-ended terms. Further, the phrase “based on” is intended to mean“based, at least in part, on” unless explicitly stated otherwise.

What is claimed is:
 1. A method of wireless communication performed by anetwork entity, comprising: detecting a preamble of a random accessmessage associated with a two-step random access procedure, wherein therandom access message is received from a user equipment (UE); processinga payload of the random access message, wherein an outcome of processingthe payload is either successfully decoding the payload or failing todecode the payload; and transmitting, based at least in part ondetecting the preamble and the outcome of processing the payload, arandom access response associated with the two-step random accessprocedure, wherein the random access response includes an uplink groupgrant, a status of the uplink group grant, and an indication of a typeof the uplink group grant, for a plurality of UEs including the UE,wherein the status includes information that identifies a number ofuplink group grants included in the random access response, wherein theindication of the type of the uplink group grant is capable ofindicating that that the uplink group grant is for one of a fallbackrandom access response, a success random access response, or a shareduplink group grant, wherein preamble transmissions of the plurality ofUEs share a time and frequency occasion, and wherein the uplink groupgrant is transmitted in a set of resources shared by the fallback randomaccess response and the success random access response.
 2. The method ofclaim 1, wherein, when the outcome of processing the payload of therandom access message is failing to decode the payload, the uplink groupgrant is included in the random access response based at least in parton failing to decode the payload.
 3. The method of claim 2, wherein theuplink group grant is included in the fallback random access response.4. The method of claim 2, wherein the UE is included in the plurality ofUEs based at least in part on a timing offset associated with the UE ora UE status of the UE.
 5. The method of claim 1, wherein the uplinkgroup grant indicates a common set of time-frequency resources, amodulation and coding scheme (MCS), common information for power controlor beam management, and a physical uplink shared channel (PUSCH) hoppingflag to be used by the plurality of UEs for transmitting other randomaccess messages.
 6. The method of claim 1, wherein a demodulationreference signal (DMRS) resource configuration for the plurality of UEsis explicitly indicated in the uplink group grant.
 7. The method ofclaim 1, wherein a demodulation reference signal (DMRS) resourceconfiguration for the plurality of UEs is implicitly indicated by amapping rule associated with preamble resource indices and DMRS resourceindices configured for the plurality of UEs by the network entity. 8.The method of claim 1, wherein a timing advance (TA) command, associatedwith the UE, and a temporary cell radio network temporary identifier(TC-RNTI), associated with the UE, are transmitted separately from theuplink group grant.
 9. The method of claim 1, wherein the uplink groupgrant is an only uplink group grant included in the random accessresponse.
 10. The method of claim 1, wherein the uplink group grant isone of a plurality of uplink group grants included in the random accessresponse.
 11. The method of claim 1, wherein the random access responsefurther includes a single-UE uplink grant for another UE.
 12. The methodof claim 1, wherein the outcome of processing the payload of the randomaccess message is successfully decoding the payload, wherein the methodfurther comprises: determining, based at least in part on a payloadindication in the payload, that the UE needs to transmit additionaluplink data, wherein the uplink group grant is included in the randomaccess response based at least in part on the indication of the type ofthe uplink group grant.
 13. The method of claim 12, wherein the uplinkgroup grant is included in the success random access response.
 14. Themethod of claim 12, wherein the indication of the type of the uplinkgroup grant is provided via a buffer status report (BSR).
 15. The methodof claim 12, wherein the indication of the type of the uplink groupgrant is provided via a scheduling request (SR).
 16. The method of claim12, wherein the UE is grouped into the plurality of UEs based at leastin part on at least one of: a reference signal received power (RSRP)measurement, a channel state information (CSI) report, beam management,quality of service (QoS) handling, or a positioning-related measurement.17. The method of claim 1, wherein the indication of the type of theuplink group grant is transmitted in a downlink control information(DCI) field of a random access response physical downlink controlchannel (PDCCH).
 18. The method of claim 17, wherein the indication ofthe type of the uplink group grant is based at least in part on abitmap.
 19. The method of claim 17, wherein the DCI is associated with acyclic redundancy check (CRC), wherein the CRC is masked by a groupradio network temporary identifier (RNTI).
 20. The method of claim 17,wherein the random access response PDCCH is transmitted in a commonsearch space.
 21. The method of claim 1, further comprising constructingthe uplink group grant for the plurality of UEs performing a two-steprandom access procedure.
 22. A method of wireless communicationperformed by a user equipment (UE), comprising: transmitting a preambleand a payload of a random access message associated with a two-steprandom access procedure; receiving a random access response, associatedwith the two-step random access procedure, including an uplink groupgrant, a status of the uplink group grant, and an indication of a typeof the uplink group grant for a plurality of UEs including the UE,wherein the status includes information that identifies a number ofuplink group grants included in the random access response, wherein theindication of the type of the uplink group grant is capable ofindicating that that the uplink group grant is for one of a fallbackrandom access response, a success random access response, or a shareduplink group grant, and wherein the uplink group grant is transmitted ina set of resources shared by the fallback random access response and thesuccess random access response; and transmitting an uplink communicationon a set of shared time-frequency resources based at least in part onthe uplink group grant.
 23. The method of claim 22, wherein the uplinkgroup grant included in the random access response indicates a networkentity failing to decode the payload.
 24. The method of claim 23,wherein the uplink group grant is included in the fallback random accessresponse.
 25. The method of claim 23, wherein the UE is included in theplurality of UEs based at least in part on a timing offset associatedwith the UE or a UE status of the UE.
 26. The method of claim 22,wherein the uplink group grant indicates a common set of time-frequencyresources, a modulation and coding scheme (MCS), common information forpower control or beam management, and a physical uplink shared channel(PUSCH) hopping flag to be used by the plurality of UEs for transmittingother random access messages.
 27. The method of claim 22, wherein ademodulation reference signal (DMRS) resource configuration for theplurality of UEs is explicitly indicated in the uplink group grant. 28.The method of claim 22, wherein a demodulation reference signal (DMRS)resource configuration for the plurality of UEs is implicitly indicatedby a mapping rule associated with preamble resource indices and DMRSresource indices configured for the plurality of UEs by a networkentity.
 29. The method of claim 22, wherein a timing advance (TA)command, associated with the UE, and a temporary cell radio networktemporary identifier (TC-RNTI), associated with the UE, are receivedseparately from the uplink group grant.
 30. The method of claim 22,wherein the uplink group grant is an only uplink group grant included inthe random access response.
 31. The method of claim 22, wherein theuplink group grant is one of a plurality of uplink group grants includedin the random access response.
 32. The method of claim 22, wherein therandom access response further includes a single-UE uplink grant foranother UE.
 33. The method of claim 22, wherein an indication that theUE needs to transmit additional uplink data is included in the payloadof the random access message.
 34. The method of claim 33, wherein theuplink group grant is included in the success random access response.35. The method of claim 33, wherein the indication of the type of theuplink group grant is provided via a buffer status report (BSR).
 36. Themethod of claim 33, wherein the indication of the type of the uplinkgroup grant is provided via a scheduling request (SR).
 37. The method ofclaim 33, wherein the UE is grouped into the plurality of UEs based atleast in part on at least one of: a reference signal received power(RSRP) measurement, a channel state information (CSI) report, beammanagement, quality of service (QoS) handling, or a positioning-relatedmeasurement.
 38. The method of claim 22, wherein the indication of thetype of the uplink group grant is received in a downlink controlinformation (DCI) field of a random access response physical downlinkcontrol channel (PDCCH) based at least in part on monitoring the randomaccess response PDCCH.
 39. The method of claim 38, wherein the DCI isassociated with a cyclic redundancy check (CRC), wherein the CRC isde-masked with a group radio network temporary identifier (RNTI). 40.The method of claim 38, wherein the DCI is decoded to determine aresource assignment of a random access response physical downlink sharedchannel (PDSCH), wherein the indication of the type of the uplink groupgrant is carried in the random access response PDSCH.
 41. The method ofclaim 22, wherein the random access response and the uplink group grantare decoded.
 42. The method of claim 22, wherein a timing advance (TA),a modulation and coding scheme (MCS), power control, beam management,and time-frequency resource allocation are applied in association withtransmitting the uplink communication.
 43. The method of claim 22,wherein the further includes: the indication of the type of the uplinkgroup grant.
 44. A network entity for wireless communication,comprising: a memory; and one or more processors coupled to the memory,the one or more processors configured to: detect a preamble of a randomaccess message associated with a two-step random access procedure,wherein the random access message is received from a user equipment(UE); process a payload of the random access message, wherein an outcomeof processing the payload is either successfully decoding the payload orfailing to decode the payload; and transmit, based at least in part ondetecting the preamble and the outcome of processing the payload, arandom access response associated with the two-step random accessprocedure, wherein the random access response includes an uplink groupgrant, a status of the uplink group grant, and an indication of a typeof the uplink group grant, for a plurality of UEs including the UE,wherein the status includes information that identifies a number ofuplink group grants included in the random access response, wherein theindication of the type of the uplink group grant is capable ofindicating that that the uplink group grant is for one of a fallbackrandom access response, a success random access response, or a shareduplink group grant, wherein preamble transmissions of the plurality ofUEs share a time and frequency occasion, and wherein the uplink groupgrant is transmitted in a set of resources shared by the fallback randomaccess response and the success random access response.
 45. The networkentity of claim 44, wherein the uplink group grant is one of a pluralityof uplink group grants included in the random access response.
 46. Thenetwork entity of claim 44, wherein an indication that the UE needs totransmit additional uplink data is included in the payload of the randomaccess message.
 47. A user equipment (UE) for wireless communication,comprising: a memory; and one or more processors coupled to the memory,the one or more processors configured to: transmit a preamble and apayload of a random access message associated with a two-step randomaccess procedure; receive a random access response, associated with thetwo-step random access procedure, including an uplink group grant, astatus of the uplink group grant, and an indication of a type of theuplink group grant for a plurality of UEs including the UE, wherein thestatus includes information that identifies a number of uplink groupgrants included in the random access response, wherein the indication ofthe type of the uplink group grant is capable of indicating that thatthe uplink group grant is for one of a fallback random access response,a success random access response, or a shared uplink group grant, andwherein the uplink group grant is transmitted in a set of resourcesshared by the fallback random access response and the success randomaccess response; and transmit an uplink communication on a set of sharedtime-frequency resources based at least in part on the uplink groupgrant.
 48. The UE of claim 47, wherein the uplink group grant is one ofa plurality of uplink group grants included in the random accessresponse.
 49. The UE of claim 47, wherein an indication that the UEneeds to transmit additional uplink data is included in the payload ofthe random access message.